What is the LCM of 9 and 21?
The LCM of 9 and 21 is 63.
Steps to find LCM
- Find the prime factorization of 9
9 = 3 × 3 - Find the prime factorization of 21
21 = 3 × 7 - Multiply each factor the greater number of times it occurs in steps i) or ii) above to find the LCM:
LCM = 3 × 3 × 7 - LCM = 63
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Find least common multiple (LCM) of: 18 & 42 27 & 63 3 & 7 45 & 105 63 & 147 18 & 21 9 & 42 27 & 21 9 & 63 45 & 21 9 & 105 63 & 21 9 & 147
LCM Calculator
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